added health check

Author: arcticfloyd1984

src/server/app.ts

@@ -82,6 +82,11 @@ app.route("/health").get((req, res) => {
   res.send("ok");
 });
 
+app.route('/:chainId/health')
+  .get((req, res) => {
+    res.send('ok');
+  });
+
 // error handler
 app.use(
   (